Nearly 17 years after the deadly Fort Hood shooting, the man convicted of carrying out the attack is now facing a final step toward execution.

President Donald Trump has approved the execution of former U.S. Army Maj. Nidal Malik Hasan by firing squad, the Pentagon announced Monday.

The recommendation came from Defense Secretary Pete Hegseth.

Pentagon spokesperson Sean Parnell announced the decision, saying the Secretary of the Army will determine the time and place of the execution.

That means Hasan does not yet have an execution date.

The decision brings renewed attention to one of the deadliest attacks ever carried out on a U.S. military installation.

On November 5, 2009, Hasan opened fire inside a medical facility at Fort Hood in Texas.

Thirteen people were killed and 32 others were wounded.

Hasan, an Army psychiatrist, was shot by a responding police officer and survived but was left partially paralyzed.

He was later prosecuted in a military court.

In 2013, a military jury found Hasan guilty of 45 counts of premeditated murder and attempted premeditated murder.

He was sentenced to death.

Hasan represented himself during much of the court-martial and made little effort to contest responsibility for the shooting.

During the trial, he said he carried out the attack to stop U.S. soldiers from deploying to Afghanistan and killing fellow Muslims.

His death sentence has remained tied up in the military appeals process for years.

The Trump administration's decision now moves the case closer to an execution, but it does not mean the execution will happen immediately.

According to ABC News, Army policy provides a window for carrying out a military execution after presidential approval, while legal appeals can also affect the timeline.

If the execution is carried out, it would be the first U.S. military execution since 1961.

It would also mark an exceptionally rare use of a firing squad by the U.S. military.

The last known U.S. military firing squad execution took place in 1945.

The decision is also significant because the U.S. military has carried out very few executions in modern history.

Hasan remains on military death row at the U.S. Disciplinary Barracks at Fort Leavenworth, Kansas.

For the families of the victims, the case has remained an unresolved chapter for nearly two decades.

Now, after years of appeals and legal proceedings, the Army has been directed to begin the process of determining when and where Nidal Hasan will face execution.

The date has not yet been announced.

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